All computer programmers should know certain data structures. These include representations of machine data, such as floating points and bit access, and hash tables, such as maps and dictionaries. Some of the most common data structures include trees, arrays, stacks, graphs, queues and databases. Computer programming relies on the use of abstractions because programs may be understood and verified through laws that govern the abstractions. Computer programmers must have an understanding of the widely used techniques for representing programming abstractions, such as the data structures, in order to make sensible decisions about program’s design and development.
The array is one of the most widely used data structure among programs. Sometimes, it is the only data structure available in certain languages. An array is a group of identical components, which is referred to as a base type or homogeneous structure. An array is a randomly accessed structure that offers equally fast and random access to all components. An individual component is denoted by the name of the augmented structure on the index. An individual array component, or a subscripted variable, can be selected by an index. The most common way of using large arrays is to selectively update individual components instead of creating new structured values.
Record structures occur when programmers join elements of arbitrary types to obtain structured types and transform them into a compound. This programming requires mathematics, real numbers and point coordinates. The most common example from database processing is describing people by set characteristics, such as their gender, dates of birth and first and last names. The mathematics behind this compound type is referred to as a Cartesian product.
The set of values defined by the compound type consist of all possible value combinations, so the number of each combinations is the logical product of the number of elements in each set.
Hash tables, which may be called hash maps or dictionaries, are a data structure that pairs keys to set values. Hash tables take on standard time for insertions and can use many object types. Hash tables are not ordered, which means the keys do not remain in the same order. Some programmers consider hash tables to be a type of indexed array because hash tables are built on arrays. In fact, programmers who need to create a hash table with sequential integers usually just create an array instead. Hash tables have an average lookup cost and case insertion.
Databases are used to store information in a computer. They are comprised of fields, records and tables. Fields are information categories, which are usually things like name, data and subject. Once fields of information are gathered together, they form a record, which in turn forms a collective table. The field type indicates what type of information is stored, such as text, dates, whole numbers, decimal numbers and Boolean questions, which are either yes or no. Field types facilitate logical sorting, so each record should contain unique information. This is normally the contents of the key field.
Tree data structures are one of the most powerful tool for organizing key-based data objects and multiple data objects in hierarchical relationships. Tree structures usually resemble an image of a genealogical family tree with data being hierarchically arranged from top to bottom. The nodes at the root are the tree’s starting point and the arcs between nodes are referred to as branches. A node without any branches is called a leaf. While real trees grow from their root ups, programming trees grow from the root downs.
Computer programmers should also know common algorithms related to sorting, such as merge and bubble sort, and searching, such as linear and binary searches.